Six women with acute calcific periarthritis of the first metatarsophalangeal joint (hydroxyapatite pseudopodagra) are described, and 10 previously reported cases (8 female patients and 2 male patients) are reviewed. The onset was characterized by acute pain, swelling, erythema, tenderness, and limitation of movement of the first metatarsophalangeal joint, symptoms indistinguishable from those of gouty podagra, which is associated with transient amorphous calcific deposits in the vicinity of the joint. Based on these results it appears that hydroxyapatite pseudopodagra is a disorder that predominantly affects premenopausal women.Acute calcific periarthritis (ACP) is a disorder characterized by acute periarticular inflammation associated with juxtaarticular deposits of calcium hydroxyapatite (1-3). Both sexes are equally affected, most commonly between the ages of 40 and 60 years (1,3). The majority of cases are sporadic and idiopathic, although there are rare familial forms, and the syndrome has also been described in association with long-term hemodialysis for renal insufficiency (2,3). The calcific deposits are usually monarticular, although they can be polyarticular and recurrent (3). The shoulder is the most commonly affected site, followed by the hip, knee, elbow, wrist, and ankle joints. Involvement of the joints of the feet and toes is rare, accounting for <1% of all cases (1).During a 1-year period, we treated 3 young women with ACP of the first metatarsophalangeal (MTP) joint. This prompted us to restudy 3 patients previously seen at our institution, and to review the literature. Our results indicate that ACP of the first MTP joint is an uncommon cause of pseudopodagra ( 4 3 , and that the disorder predominantly affects premenopausal women.
PATIENTS AND METHODSPatients. Three young women with ACP of the first MTP joint were seen within a I-year period by one of us (AGF), prompting this investigation. Subsequently, the records of 3 patients treated previously at Sunnybrook Medical Centre, including 2 previously reported cases (2), were reviewed, and a computer-assisted literature search was carried out. Criteria for entry into the study included the acute onset of localized pain, swelling, and tenderness at the base of the great toe, together with radiologic evidence of corresponding, amorphous calcification in the periarticular tissues of the first MTP joint. No patient had gout, pseudogout, or diseases associated with subcutaneous calcinosis, such as scleroderma.Clinical evaluation. A retrospective analysis was done of the following historical data: age, sex, mode of presentation, prior trauma to or overuse of the joint, description and duration of the acute attack, initial diagnosis, time required for proper diagnosis, associated medical illnesses, previous episodes, and familial occurrence.General physical and musculoskeletal examinations were performed. Patients were evaluated for any underlying
